Christoph Hellwig <hch@xxxxxxxxxxxxx> writes:
> On Thu, Dec 17, 2009 at 11:30:36AM -0500, tytso@xxxxxxx wrote:
>> That's because apparently the iSCSI and DMA blocks assume that they
>> have Real Pages (tm) passed to block I/O requests, and apparently XFS
>> ran into problems when sending vmalloc'ed pages. I don't know if this
>> is a problem if we pass the bio layer addresses coming from the SLAB
>> allocator, but oral tradition seems to indicate this is problematic,
>> although no one has given me the full chapter and verse explanation
>> about why this is so.
>
> Actually at least iscsi now has a workaround for that by checking for
> PageSlab. Back when we deal with the XFS issue that check was only
> available with debug options enabled. I tried to sort it out by
> agreeing with the block and iscsi folks that either
DRBD has the same workaround as well:
if (disable_sendpage || (page_count(page) < 1) || PageSlab(page))
But it seems like a gross hack to me. Perhaps this should be
passed as some sort of BIO attribute?
-Andi
--
ak@xxxxxxxxxxxxxxx -- Speaking for myself only.
--
To unsubscribe from this list: send the line "unsubscribe linux-parisc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
